Telomere-to-telomere gap-free genome assembly of Euchiloglanis kishinouyei.

Euchiloglanis kishinouyei is a typical endemic torrent catfish found in the Jinsha River system of the upper Yangtze River in China. It inhabits fast-flowing streams with steep elevation gradients and has evolved unique biological adaptations to thrive in these extreme environments. A high-quality genome provides key insights into the adaptive mechanisms driving its evolution in these harsh conditions. In this study, we successfully assembled the first telomere-to-telomere (T2T) genome of E. kishinouyei, marking the first T2T genome assembly of torrent catfish. The genome spans 886.74 Mb, anchored to 27 chromosomes, with over 99% coverage. The quality value (QV) and Benchmarking Universal Single-Copy Ortholog (BUSCO) scores were 46.96 and 98.50%, respectively, reflecting the high quality of the assembly. We identified repetitive elements accounting for 45.59% (404.23 Mb) of the genome and predicted 24,403 protein-coding genes, 94.37% of which were annotated. This high-fidelity genome assembly provides a valuable resource for future research and lays the foundation for exploring the ecological adaptation mechanisms and evolutionary biology of torrent catfish.